When I put the rich:tooltip outside the inputText but inside the panelGroup the tooltip is shown on hovering the inputText, but it creates ugly artifacts for subsequent components. It's supposed to be displayed only above the inputText.

I tried wrapping the h:inputText into a4j:outputPanel (no attributes), but that didn't work either.

It's not working. I had tried this before and all possible combinations of ID, target, and in/outside the inputText - no tooltip displayed. Appears to be a more severe bug. This is really basic stuff in RF not working.

The problem with my code is that I placed the tooltip as an sub element inside the inputText. Putting them outside seems to be mandatory.

The disabled thing you have demonstrated is really true. The next question would be if tooltips should automatically be hidden for disabled elements and/or if there should be a flag on the tooltip to override the behavior on disabled components.